rpc.subproj/svc_udp.c

   1 /*
   2  * Copyright (c) 1999-2018 Apple Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * Portions Copyright (c) 1999 Apple Computer, Inc.  All Rights
   7  * Reserved.  This file contains Original Code and/or Modifications of
   8  * Original Code as defined in and that are subject to the Apple Public
   9  * Source License Version 1.1 (the "License").  You may not use this file
  10  * except in compliance with the License.  Please obtain a copy of the
  11  * License at http://www.apple.com/publicsource and read it before using
  12  * this file.
  13  *
  14  * The Original Code and all software distributed under the License are
  15  * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  16  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  17  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE OR NON- INFRINGEMENT.  Please see the
  19  * License for the specific language governing rights and limitations
  20  * under the License.
  21  *
  22  * @APPLE_LICENSE_HEADER_END@
  23  */
  24 /*
  25  * Sun RPC is a product of Sun Microsystems, Inc. and is provided for
  26  * unrestricted use provided that this legend is included on all tape
  27  * media and as a part of the software program in whole or part.  Users
  28  * may copy or modify Sun RPC without charge, but are not authorized
  29  * to license or distribute it to anyone else except as part of a product or
  30  * program developed by the user.
  31  *
  32  * SUN RPC IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING THE
  33  * WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
  34  * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
  35  *
  36  * Sun RPC is provided with no support and without any obligation on the
  37  * part of Sun Microsystems, Inc. to assist in its use, correction,
  38  * modification or enhancement.
  39  *
  40  * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
  41  * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY SUN RPC
  42  * OR ANY PART THEREOF.
  43  *
  44  * In no event will Sun Microsystems, Inc. be liable for any lost revenue
  45  * or profits or other special, indirect and consequential damages, even if
  46  * Sun has been advised of the possibility of such damages.
  47  *
  48  * Sun Microsystems, Inc.
  49  * 2550 Garcia Avenue
  50  * Mountain View, California  94043
  51  */
  52
  53 #if defined(LIBC_SCCS) && !defined(lint)
  54 /*static char *sccsid = "from: @(#)svc_udp.c 1.24 87/08/11 Copyr 1984 Sun Micro";*/
  55 /*static char *sccsid = "from: @(#)svc_udp.c    2.2 88/07/29 4.0 RPCSRC";*/
  56 static char *rcsid = "$Id: svc_udp.c,v 1.5 2004/10/13 00:24:07 jkh Exp $";
  57 #endif
  58
  59 /*
  60  * svc_udp.c,
  61  * Server side for UDP/IP based RPC.  (Does some caching in the hopes of
  62  * achieving execute-at-most-once semantics.)
  63  *
  64  * Copyright (C) 1984, Sun Microsystems, Inc.
  65  */
  66
  67 #include "libinfo_common.h"
  68
  69 #include <stdio.h>
  70 #include <stdlib.h>
  71 #include <stdint.h>
  72 #include <string.h>
  73 #include <unistd.h>
  74 #include <rpc/rpc.h>
  75 #include <sys/socket.h>
  76 #include <sys/param.h>
  77 #include <errno.h>
  78
  79 extern int              bindresvport();
  80
  81 #define rpc_buffer(xprt) ((xprt)->xp_p1)
  82
  83 static bool_t           svcudp_recv();
  84 static bool_t           svcudp_reply();
  85 static enum xprt_stat   svcudp_stat();
  86 static bool_t           svcudp_getargs();
  87 static bool_t           svcudp_freeargs();
  88 static void             svcudp_destroy();
  89
  90 static struct xp_ops svcudp_op = {
  91         svcudp_recv,
  92         svcudp_stat,
  93         svcudp_getargs,
  94         svcudp_reply,
  95         svcudp_freeargs,
  96         svcudp_destroy
  97 };
  98
  99 extern int errno;
 100
 101 /*
 102  * kept in xprt->xp_p2
 103  */
 104 struct svcudp_data {
 105         u_int   su_iosz;        /* byte size of send.recv buffer */
 106 #ifdef __LP64__
 107         uint32_t        su_xid;         /* transaction id */
 108 #else
 109         u_long  su_xid;         /* transaction id */
 110 #endif
 111         XDR     su_xdrs;        /* XDR handle */
 112         char    su_verfbody[MAX_AUTH_BYTES];    /* verifier body */
 113         char *  su_cache;       /* cached data, NULL if no cache */
 114 };
 115 #define su_data(xprt)   ((struct svcudp_data *)(xprt->xp_p2))
 116
 117 /*
 118  * Usage:
 119  *      xprt = svcudp_create(sock);
 120  *
 121  * If sock<0 then a socket is created, else sock is used.
 122  * If the socket, sock is not bound to a port then svcudp_create
 123  * binds it to an arbitrary port.  In any (successful) case,
 124  * xprt->xp_sock is the registered socket number and xprt->xp_port is the
 125  * associated port number.
 126  * Once *xprt is initialized, it is registered as a transporter;
 127  * see (svc.h, xprt_register).
 128  * The routines returns NULL if a problem occurred.
 129  */
 130 LIBINFO_EXPORT
 131 SVCXPRT *
 132 svcudp_bufcreate(sock, sendsz, recvsz)
 133         register int sock;
 134         u_int sendsz, recvsz;
 135 {
 136         bool_t madesock = FALSE;
 137         register SVCXPRT *xprt;
 138         register struct svcudp_data *su;
 139         struct sockaddr_in addr;
 140         unsigned int len = sizeof(struct sockaddr_in);
 141
 142         if (sock == RPC_ANYSOCK) {
 143                 if ((sock = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP)) < 0) {
 144                         perror("svcudp_create: socket creation problem");
 145                         return ((SVCXPRT *)NULL);
 146                 }
 147                 madesock = TRUE;
 148         }
 149         bzero((char *)&addr, sizeof (addr));
 150         addr.sin_family = AF_INET;
 151         if (bindresvport(sock, &addr)) {
 152                 addr.sin_port = 0;
 153                 (void)bind(sock, (struct sockaddr *)&addr, len);
 154         }
 155         if (getsockname(sock, (struct sockaddr *)&addr, &len) != 0) {
 156                 perror("svcudp_create - cannot getsockname");
 157                 if (madesock)
 158                         (void)close(sock);
 159                 return ((SVCXPRT *)NULL);
 160         }
 161         xprt = (SVCXPRT *)mem_alloc(sizeof(SVCXPRT));
 162         if (xprt == NULL) {
 163                 (void)fprintf(stderr, "svcudp_create: out of memory\n");
 164                 return (NULL);
 165         }
 166         su = (struct svcudp_data *)mem_alloc(sizeof(*su));
 167         if (su == NULL) {
 168                 mem_free(xprt, sizeof(SVCXPRT));
 169                 (void)fprintf(stderr, "svcudp_create: out of memory\n");
 170                 return (NULL);
 171         }
 172         su->su_iosz = ((MAX(sendsz, recvsz) + 3) / 4) * 4;
 173         if ((rpc_buffer(xprt) = mem_alloc(su->su_iosz)) == NULL) {
 174                 mem_free(xprt, sizeof(SVCXPRT));
 175                 mem_free(su, sizeof(*su));
 176                 (void)fprintf(stderr, "svcudp_create: out of memory\n");
 177                 return (NULL);
 178         }
 179         xdrmem_create(
 180             &(su->su_xdrs), rpc_buffer(xprt), su->su_iosz, XDR_DECODE);
 181         su->su_cache = NULL;
 182         xprt->xp_p2 = (caddr_t)su;
 183         xprt->xp_verf.oa_base = su->su_verfbody;
 184         xprt->xp_ops = &svcudp_op;
 185         xprt->xp_port = ntohs(addr.sin_port);
 186         xprt->xp_sock = sock;
 187         xprt_register(xprt);
 188         return (xprt);
 189 }
 190
 191 LIBINFO_EXPORT
 192 SVCXPRT *
 193 svcudp_create(sock)
 194         int sock;
 195 {
 196
 197         return(svcudp_bufcreate(sock, UDPMSGSIZE, UDPMSGSIZE));
 198 }
 199
 200 static enum xprt_stat
 201 svcudp_stat(xprt)
 202         SVCXPRT *xprt;
 203 {
 204
 205         return (XPRT_IDLE);
 206 }
 207
 208 static int cache_get();
 209 static void cache_set();
 210
 211 static bool_t
 212 svcudp_recv(xprt, msg)
 213         register SVCXPRT *xprt;
 214         struct rpc_msg *msg;
 215 {
 216         register struct svcudp_data *su = su_data(xprt);
 217         register XDR *xdrs = &(su->su_xdrs);
 218         register int rlen;
 219         char *reply;
 220 #ifdef __LP64__
 221         uint32_t replylen;
 222 #else
 223         u_long replylen;
 224 #endif
 225
 226     again:
 227         xprt->xp_addrlen = sizeof(struct sockaddr_in);
 228         rlen = recvfrom(xprt->xp_sock, rpc_buffer(xprt), (int) su->su_iosz, 0, (struct sockaddr *)&(xprt->xp_raddr), (unsigned int *)&(xprt->xp_addrlen));
 229         if (rlen == -1 && errno == EINTR)
 230                 goto again;
 231 #ifdef __LP64__
 232         if (rlen < 4*sizeof(uint32_t))
 233                 return (FALSE);
 234 #else
 235         if (rlen < 4*sizeof(u_long))
 236                 return (FALSE);
 237 #endif
 238         xdrs->x_op = XDR_DECODE;
 239         XDR_SETPOS(xdrs, 0);
 240         if (! xdr_callmsg(xdrs, msg))
 241                 return (FALSE);
 242         su->su_xid = msg->rm_xid;
 243         if (su->su_cache != NULL) {
 244                 if (cache_get(xprt, msg, &reply, &replylen)) {
 245                         (void) sendto(xprt->xp_sock, reply, (int) replylen, 0,
 246                           (struct sockaddr *) &xprt->xp_raddr, xprt->xp_addrlen);
 247                         return (TRUE);
 248                 }
 249         }
 250         return (TRUE);
 251 }
 252
 253 static bool_t
 254 svcudp_reply(xprt, msg)
 255         register SVCXPRT *xprt;
 256         struct rpc_msg *msg;
 257 {
 258         register struct svcudp_data *su = su_data(xprt);
 259         register XDR *xdrs = &(su->su_xdrs);
 260         register int slen;
 261         register bool_t stat = FALSE;
 262
 263         xdrs->x_op = XDR_ENCODE;
 264         XDR_SETPOS(xdrs, 0);
 265         msg->rm_xid = su->su_xid;
 266         if (xdr_replymsg(xdrs, msg)) {
 267                 slen = (int)XDR_GETPOS(xdrs);
 268                 if (sendto(xprt->xp_sock, rpc_buffer(xprt), slen, 0,
 269                     (struct sockaddr *)&(xprt->xp_raddr), xprt->xp_addrlen)
 270                     == slen) {
 271                         stat = TRUE;
 272                         if (su->su_cache && slen >= 0) {
 273 #ifdef __LP64__
 274                                 cache_set(xprt, (uint32_t) slen);
 275 #else
 276                                 cache_set(xprt, (u_long) slen);
 277 #endif
 278                         }
 279                 }
 280         }
 281         return (stat);
 282 }
 283
 284 static bool_t
 285 svcudp_getargs(xprt, xdr_args, args_ptr)
 286         SVCXPRT *xprt;
 287         xdrproc_t xdr_args;
 288         caddr_t args_ptr;
 289 {
 290
 291         return ((*xdr_args)(&(su_data(xprt)->su_xdrs), args_ptr, 0));
 292 }
 293
 294 static bool_t
 295 svcudp_freeargs(xprt, xdr_args, args_ptr)
 296         SVCXPRT *xprt;
 297         xdrproc_t xdr_args;
 298         caddr_t args_ptr;
 299 {
 300         register XDR *xdrs = &(su_data(xprt)->su_xdrs);
 301
 302         xdrs->x_op = XDR_FREE;
 303         return ((*xdr_args)(xdrs, args_ptr, 0));
 304 }
 305
 306 static void
 307 svcudp_destroy(xprt)
 308         register SVCXPRT *xprt;
 309 {
 310         register struct svcudp_data *su = su_data(xprt);
 311
 312         xprt_unregister(xprt);
 313         (void)close(xprt->xp_sock);
 314         XDR_DESTROY(&(su->su_xdrs));
 315         mem_free(rpc_buffer(xprt), su->su_iosz);
 316         mem_free((caddr_t)su, sizeof(struct svcudp_data));
 317         mem_free((caddr_t)xprt, sizeof(SVCXPRT));
 318 }
 319
 320
 321 /***********this could be a separate file*********************/
 322
 323 /*
 324  * Fifo cache for udp server
 325  * Copies pointers to reply buffers into fifo cache
 326  * Buffers are sent again if retransmissions are detected.
 327  */
 328
 329 #define SPARSENESS 4    /* 75% sparse */
 330
 331 #define CACHE_PERROR(msg)       \
 332         (void) fprintf(stderr,"%s\n", msg)
 333
 334 #define ALLOC(type, size)       \
 335         (type *) mem_alloc((unsigned) (sizeof(type) * (size)))
 336
 337 #define BZERO(addr, type, size)  \
 338         bzero((char *) addr, sizeof(type) * (int) (size))
 339
 340 /*
 341  * An entry in the cache
 342  */
 343 typedef struct cache_node *cache_ptr;
 344 struct cache_node {
 345         /*
 346          * Index into cache is xid, proc, vers, prog and address
 347          */
 348 #ifdef __LP64__
 349         uint32_t cache_xid;
 350         uint32_t cache_proc;
 351         uint32_t cache_vers;
 352         uint32_t cache_prog;
 353 #else
 354         u_long cache_xid;
 355         u_long cache_proc;
 356         u_long cache_vers;
 357         u_long cache_prog;
 358 #endif
 359         struct sockaddr_in cache_addr;
 360         /*
 361          * The cached reply and length
 362          */
 363         char * cache_reply;
 364 #ifdef __LP64__
 365         uint32_t cache_replylen;
 366 #else
 367         u_long cache_replylen;
 368 #endif
 369         /*
 370          * Next node on the list, if there is a collision
 371          */
 372         cache_ptr cache_next;
 373 };
 374
 375
 376
 377 /*
 378  * The entire cache
 379  */
 380 struct udp_cache {
 381 #ifdef __LP64__
 382         uint32_t uc_size;               /* size of cache */
 383 #else
 384         u_long uc_size;         /* size of cache */
 385 #endif
 386         cache_ptr *uc_entries;  /* hash table of entries in cache */
 387         cache_ptr *uc_fifo;     /* fifo list of entries in cache */
 388 #ifdef __LP64__
 389         uint32_t uc_nextvictim; /* points to next victim in fifo list */
 390         uint32_t uc_prog;               /* saved program number */
 391         uint32_t uc_vers;               /* saved version number */
 392         uint32_t uc_proc;               /* saved procedure number */
 393 #else
 394         u_long uc_nextvictim;   /* points to next victim in fifo list */
 395         u_long uc_prog;         /* saved program number */
 396         u_long uc_vers;         /* saved version number */
 397         u_long uc_proc;         /* saved procedure number */
 398 #endif
 399         struct sockaddr_in uc_addr; /* saved caller's address */
 400 };
 401
 402
 403 /*
 404  * the hashing function
 405  */
 406 #define CACHE_LOC(transp, xid)  \
 407  (xid % (SPARSENESS*((struct udp_cache *) su_data(transp)->su_cache)->uc_size))
 408
 409
 410 /*
 411  * Enable use of the cache.
 412  * Note: there is no disable.
 413  */
 414 int
 415 svcudp_enablecache(transp, size)
 416         SVCXPRT *transp;
 417 #ifdef __LP64__
 418         uint32_t size;
 419 #else
 420         u_long size;
 421 #endif
 422 {
 423         struct svcudp_data *su = su_data(transp);
 424         struct udp_cache *uc;
 425
 426         if (su->su_cache != NULL) {
 427                 CACHE_PERROR("enablecache: cache already enabled");
 428                 return(0);
 429         }
 430         uc = ALLOC(struct udp_cache, 1);
 431         if (uc == NULL) {
 432                 CACHE_PERROR("enablecache: could not allocate cache");
 433                 return(0);
 434         }
 435         uc->uc_size = size;
 436         uc->uc_nextvictim = 0;
 437         uc->uc_entries = ALLOC(cache_ptr, size * SPARSENESS);
 438         if (uc->uc_entries == NULL) {
 439                 mem_free(uc, sizeof(*uc));
 440                 CACHE_PERROR("enablecache: could not allocate cache data");
 441                 return(0);
 442         }
 443         BZERO(uc->uc_entries, cache_ptr, size * SPARSENESS);
 444         uc->uc_fifo = ALLOC(cache_ptr, size);
 445         if (uc->uc_fifo == NULL) {
 446                 mem_free(uc->uc_entries, sizeof(struct udp_cache)*size * SPARSENESS);
 447                 mem_free(uc, sizeof(struct udp_cache));
 448                 CACHE_PERROR("enablecache: could not allocate cache fifo");
 449                 return(0);
 450         }
 451         BZERO(uc->uc_fifo, cache_ptr, size);
 452         su->su_cache = (char *) uc;
 453         return(1);
 454 }
 455
 456
 457 /*
 458  * Set an entry in the cache
 459  */
 460 static void
 461 cache_set(xprt, replylen)
 462         SVCXPRT *xprt;
 463 #ifdef __LP64__
 464         uint32_t replylen;
 465 #else
 466         u_long replylen;
 467 #endif
 468 {
 469         register cache_ptr victim;
 470         register cache_ptr *vicp;
 471         register struct svcudp_data *su = su_data(xprt);
 472         struct udp_cache *uc = (struct udp_cache *) su->su_cache;
 473         u_int loc;
 474         char *newbuf;
 475
 476         /*
 477          * Find space for the new entry, either by
 478          * reusing an old entry, or by mallocing a new one
 479          */
 480         victim = uc->uc_fifo[uc->uc_nextvictim];
 481         if (victim != NULL) {
 482                 loc = CACHE_LOC(xprt, victim->cache_xid);
 483                 for (vicp = &uc->uc_entries[loc];
 484                   *vicp != NULL && *vicp != victim;
 485                   vicp = &(*vicp)->cache_next)
 486                                 ;
 487                 if (*vicp == NULL) {
 488                         CACHE_PERROR("cache_set: victim not found");
 489                         return;
 490                 }
 491                 *vicp = victim->cache_next;     /* remote from cache */
 492                 newbuf = victim->cache_reply;
 493         } else {
 494                 victim = ALLOC(struct cache_node, 1);
 495                 if (victim == NULL) {
 496                         CACHE_PERROR("cache_set: victim alloc failed");
 497                         return;
 498                 }
 499                 newbuf = mem_alloc(su->su_iosz);
 500                 if (newbuf == NULL) {
 501                         mem_free(victim, sizeof(*victim));
 502                         CACHE_PERROR("cache_set: could not allocate new rpc_buffer");
 503                         return;
 504                 }
 505         }
 506
 507         /*
 508          * Store it away
 509          */
 510         victim->cache_replylen = replylen;
 511         victim->cache_reply = rpc_buffer(xprt);
 512         rpc_buffer(xprt) = newbuf;
 513         xdrmem_create(&(su->su_xdrs), rpc_buffer(xprt), su->su_iosz, XDR_ENCODE);
 514         victim->cache_xid = su->su_xid;
 515         victim->cache_proc = uc->uc_proc;
 516         victim->cache_vers = uc->uc_vers;
 517         victim->cache_prog = uc->uc_prog;
 518         victim->cache_addr = uc->uc_addr;
 519         loc = CACHE_LOC(xprt, victim->cache_xid);
 520         victim->cache_next = uc->uc_entries[loc];
 521         uc->uc_entries[loc] = victim;
 522         uc->uc_fifo[uc->uc_nextvictim++] = victim;
 523         uc->uc_nextvictim %= uc->uc_size;
 524 }
 525
 526 /*
 527  * Try to get an entry from the cache
 528  * return 1 if found, 0 if not found
 529  */
 530 static int
 531 cache_get(xprt, msg, replyp, replylenp)
 532         SVCXPRT *xprt;
 533         struct rpc_msg *msg;
 534         char **replyp;
 535 #ifdef __LP64__
 536         uint32_t *replylenp;
 537 #else
 538         u_long *replylenp;
 539 #endif
 540 {
 541         u_int loc;
 542         register cache_ptr ent;
 543         register struct svcudp_data *su = su_data(xprt);
 544         register struct udp_cache *uc = (struct udp_cache *) su->su_cache;
 545
 546 #       define EQADDR(a1, a2)   (bcmp((char*)&a1, (char*)&a2, sizeof(a1)) == 0)
 547
 548         loc = CACHE_LOC(xprt, su->su_xid);
 549         for (ent = uc->uc_entries[loc]; ent != NULL; ent = ent->cache_next) {
 550                 if (ent->cache_xid == su->su_xid &&
 551                   ent->cache_proc == uc->uc_proc &&
 552                   ent->cache_vers == uc->uc_vers &&
 553                   ent->cache_prog == uc->uc_prog &&
 554                   EQADDR(ent->cache_addr, uc->uc_addr)) {
 555                         *replyp = ent->cache_reply;
 556                         *replylenp = ent->cache_replylen;
 557                         return(1);
 558                 }
 559         }
 560         /*
 561          * Failed to find entry
 562          * Remember a few things so we can do a set later
 563          */
 564         uc->uc_proc = msg->rm_call.cb_proc;
 565         uc->uc_vers = msg->rm_call.cb_vers;
 566         uc->uc_prog = msg->rm_call.cb_prog;
 567         uc->uc_addr = xprt->xp_raddr;
 568         return(0);
 569 }
 570